DIE RHEINPFALZ | © Article & photo on top: Klaus Kadel-Magin, 4 January 2023
“Many people currently want heat pumps to keep heating costs under control. Lemberg-based PTI AG has gone one step further and has been heating with a geothermal heat pump since October. Board member Andreas Albert had acted immediately with the start of the war in Ukraine. Currently, such systems are not available until 2024.
The plant in the Lemberg industrial area on the K36 has nothing to do with geothermal energy, which causes minor earthquakes and annoyance with neighbours in Insheim near Landau. PTI has only drilled 95 metres deep. In Insheim, drilling was done up to 3800 metres deep. PTI’s system is also more like a normal heat pump, with the difference that it does not tap the outside air as a heat source, but the permanently eight to nine degrees Celsius warm layers of earth at a depth of around 100 metres.
For the size of the company’s headquarters, it would be difficult for a normal heat pump to produce a comfortable heating temperature at an outside temperature of zero or minus five degrees Celsius with reasonable electrical effort, according to PTI board member Andreas Albert. A heat pump works practically like a refrigerator, except that it is not cooled but heated. The outside air is drawn in and compressed in compressors and then condenses. This produces heat that can be used for heating. With geothermal energy, it takes significantly less electricity to heat up. With the system as operated by PTI, it would be quite possible to heat up to 60 degrees Celsius. The heat in the large office room is radiated through the ceiling.
Heat pump with refrigerator format
The heat pump gets to the heat in the depths with a brine that is chemically similar to the refrigerant glycol, explains Albert. The brine is pumped down, evaporates at eight degrees and is then compressed at the top to reach the heating temperature. With one kilowatt hour of electricity, four kilowatt hours of heat can be generated. The heat pump is located in the building at PTI and is about the size of a refrigerator. Nothing can be heard of their work in the offices. There is no sign of the borehole.
Some of the electricity for the heat pump and the farm’s many computers comes from a neighbouring hall. Solar modules have been producing around 28,000 kilowatt hours of electricity per year there since 2018. At today’s electricity prices, 14,000 euros would have to be paid for this. 45 per cent of PTI’s electricity needs could be met in this way. While other heat pumps keep a heating rod on hand for particularly cold days or even have a gas boiler in reserve, PTI’s geothermal heat pump only has to make do with the eight degrees at a depth of 95 metres.
Delivery date postponed several times
Until October, PTI heated with gas. “The system was not that old,” says Albert, who had been considering switching to a geothermal heat pump for some time. When the Ukraine war started in February, that was the signal for him to start implementing it immediately. Applications for funding were submitted, after eleven weeks the approval came from the district administration and in August drilling could begin. The neighbouring heating company Hapa did the installation of the heat pump. Even then, the delivery date was postponed three times, says Albert. “We were still lucky. Currently, delivery times of 15 to 18 months are common.”
The new heating system costs 80,000 euros. Albert hopes for a 35 per cent subsidy. The plant will probably need 15,000 kilowatt hours of electricity per year. It is likely to keep PTI up to 15 per cent below the cost of the previous gas price, he said.
The company headquarters near Lemberg, built in 1999, currently employs 30 people. In addition to the heat pump, PTI also relies on renewable energy in other ways. Three hybrid cars are already in the fleet. Two purely electric cars have been on order for 16 months, but have not yet been delivered. The vehicles can then also be charged at the photovoltaic system.
District solution would be possible
Albert is absolutely convinced of the heat pump’s technology. At his private house, a heat pump has been running for 22 years without any major malfunctions. “The technical progress here is enormous,” he says. Albert could have imagined the plant in Lemberg to be larger. A district solution with surrounding businesses, the fire brigade and the building yard would have been conceivable. Geothermal heat pumps are also suitable for schools and large administrative buildings. This is feasible in many places, as long as there is no massive rock to hinder the drilling or the building is located in a water protection area.
“If we are serious about the energy turnaround, money must be pumped in now,” says Albert, criticising the funding policy, which has been too hesitant so far. Ten years ago, for example, the promotion of renewable energies was practically stomped out, with the consequences that are now leading to the energy crisis. As an example, he cites the almost non-existent production of photovoltaic modules in Germany, which now have to be imported from the Far East with enormous delivery times.”